Combined muffler and heater



' 3 1 2 Aug 9 7 J. w. KEENAN COMBINED MUFFLEEAND HEATER I Filed Auz.,l2. 192:5.

Elm map Patented Aug. 30, 1927.

PATENT OFFICE.

JAMES W. KEENAN, 0F FARMINGTON, MICHIGAN.

COMBINED MUFFLER AND HEATER.

Application filed August 12, 1926. Serial No; 128,774.

This invention relates to new and useful improvements in combination mufliers and heaters for automobile vehicles, and has for its object the provision of a muflier which gives maximum heating surface area for the ,heater associated therewith, and which includes means to provide for the shrinkage in volume of the gases caused by the drop of temperature of the gases, whereby the efiiciency of the muflier is increased. 5 Another object of the invention is to provide a muffler having minimum back pressure. I

Other objects of the invention will appear hereinafter.

In the drawing: 1

Figure 1 is a plan view of a device illustrative of the invention and havingthe casing thereof in section; 7

' Figure 2 is a longitudinal vertical section of the same; and s Figure 3 is a cross sectional view taken on the line IIIIII of Figure 2.-

Similar characters of reference indicate corresponding parts.

Referring to the drawing The heating and muflling element, according to the present invention as shown, comprises a cast inlet header 10, a cast outlet header 11 ofsmaller dimension than the inlet header, and a sheetmetal conduit 12 connected into the said headers at its ends as indicated. at 13 (Figure 2).

The inlet header .10 is hollow and formed preferably of'cast iron, and has a depending transverse internal dividing wall 14, and an outer laterally extending supporting flange 15 formed witha central aperture in which is inserted an end of the exhaust pipe 16. Said supporting flange 15 also serves as a supporting end wall for the casing hereinafter described, and has an opening 17 to permit air to enter said casing. The inlet header 10 also has formed integral therewith or otherwise carried thereon, a series of radiating fins 18, which may be positioned on the upper side thereof as shown, or upon both sides. The outlet header 11 is also hollow and formed preferably of cast iron, and has an opening 19 within which the end of an exhaust pipe 20 is inserted, said pipe extending loosely through the central aperture 21 formed in the plate 22 forming the other end wall of the heater casing, said plate serving as a support for the outlet header 11, the connec vided with short out-turned flanges 25 (Fig.

2). Said sheets are preferably assembled out of parallelism with one another in order to gradually diminish the cross-sectional area of. the conduit near the outlet end thereof, the purpose of which will appear presently, andthe longitudinal corrugations of said walls 23 and 23*, not only increase the heat radiating area thereof but also provide for expansion and contraction of the conduit.

Headers 10 and 11 are preferably cast.

across the opposite flanged ends of the mufiler conduit 12 during the formation process of the headers, the casting of the metal of the headers around the flanged ends of said .metal' sheets being employed to effect a gas tight connection therebetween, or said headers may be welded or otherwise secured to the ends of the sheets.

The edges of the end walls 15 and 22 of the heater casing are grooved as indicated at 26 and 27 respectively to receive the ends of a sheet metal casing 28 hereinbefore. mentioned, said casing being fashioned to, conform to the shape of said end walls, and

having its longitudinal edges overlapping and riveted together as indicated at 29 (Fig. 3). Stay bolts 30 extending through suitable apertures in each of said end walls, tie said ends together and clamp the casing wall 28 therebetween.

To close the space between the longitudinal sides of the conduit 12 and the casing wall 28, longitudinal angle strips 31 may be provided if found desirable, said strips being riveted or otherwise secured to the wall 28 along one flange of each strip with the other flange engaged with or secured to the interlocked edges 24 of said sheets forming the conduit, as shown in Fig. 3, the space within the casing below the conduit being thus separated from the space above except that said spaces are in communication at the rear end of the casing beyond the header 11. The top of the casing wall 28 adjacent the said radiating fins 18, is formed with a flanged opening 32 forming an outlet end vehicle engine (not shown) rush through the exhaust pipe 16 (which is the usual exhaust pipe of the engine) into the inlet header 10 contacting with the depending wall 14: which deflects the flow abruptly, thus decreasing the velocity of travel. Moving past said flange and into the open end of the corrugated conduit 12, the gases flow therethrough within the channels formed by the corrugations, and the heat of these gases is rapidly dissipated by the thin sheet metal walls of the conduit which have a maximum heat radiating area, and the gradual decrease in the cross-sectional area of the conduit l2 provides for shrinkage in volume of exhaust gases due to drop in temperature. Furthermore, by providin a substantially straight path of flow for the exhaust gases, back pressure is reduced to a minimum, and as the gases pass into the exhaust header 11, they are somewhat retarded and permitted to expand so that as they pass out through the exhaust pipe 20, they will issue therefrom without noise.

Atmospheric air enters the heater casing through the opening 17 in the forward end wall 15 thereof and flows longitudinally of and beneath the conduit 12 in contact therewith to the rear. end of the casing, thence upward around the outlet header 11, and back to the forward end of the casing over saidconduit in contact therewith and with the fins 18 on the outlet header 11 to the outlet 32 from which the air thus heated passes into the interior of the vehicle.

A. combined exhaust mufiier and air heater is thus provided, which muflier affords a maximum of heating area to rapidly heat air which is conducted into the vehicle and in which muffler back pressure is reduced to a minimum and from which the exhaust i gases are expelled without noise. Heated air uncontaminated by exhaust gases is supplied to heat the car, and a device of simple construction and which is cheap to manufacture, is provided. Combining of muffler construction and arrangement, within the.

scope of the appended claims without departing from the present invention, and such changes are contemplated.

What I claim is 1. A combined heater and muflier including a casing having an air inlet at one end and in the lower part thereof and a hot air outlet at the same end and in the upper part thereof, a muflling device in said casing extending horizontally across the same from side to side thereof and from one end to adjacent the opposite end, said mufiiing device including a conduit .for hot gases extending longitudinally of the casing and constructed to permit expansion of hot gases passing therethrough, the walls of said consion and with its walls formed of corrugated sheet metal.

4. A combined mufiler and heater including a casing having an air inlet opening in the lower part thereof and a hot air outlet in its upper part, a mufiiing device in said casing including hollow headers and a corrugated sheet metal conduit connecting said headers, one of said headers having an inlet for hot gases and the other header having an outlet for the gases extending through the opposite end of the casing, one of said headers being spaced from the casin end and within the same and said conduit being of a width to extend horizontally across the casing and divide the same into air passages above and below said conduit, said passages being in communication at one end of said casing between the header and the end of the casing, said headers forming expansion chambers for the hot gases passing through the mufiling device and said conduit being of decreasing cross-sectional area throughout its length, whereby the hot gases passing through said device are cooled by radiation and retarded and the heat is imparted to the air passing through said casing.

In testimony whereof I aflix my signature.

JAMES w. KEEN'AN. 

